1. Field of the Invention
The present general inventive concept relates to an image drum and a manufacturing method thereof. More particularly, the present general inventive concept relates to an image drum which is used to an image forming apparatus for direct printing, and a manufacturing method thereof.
2. Description of the Related Art
An image forming apparatus for direct printing transmits an image signal directly to an image drum and forms an image by developing the image signal, so that a light exposure device or an electric charge device which is used for an electrophotographic image forming apparatus is not required. In addition, since the image forming apparatus for direct printing has secure features in its processing, the image forming apparatus for direct printing is constantly developing.
A conventional image drum used for the image forming apparatus for direct printing generally includes a drum body having a cylindrical shape, a plurality of ring electrodes formed on an external surface of the drum body, and a control circuit board formed inside the drum body.
The drum body is formed of aluminum or an aluminum alloy. The plurality of ring electrodes is insulated from neighboring electrodes by an insulation layer which is formed on the external surface of the drum body, and insulated with the drum body. Each ring electrode is electrically connected to a terminal installed on the control circuit board through a through hole formed in the drum body.
The terminal on the control circuit board is electrically connected to each ring electrode by a zebra strip. The control circuit board applies an appropriate voltage to the ring electrodes according to image information, and a latent image is thereby formed on the image drum.
Since the image drum generally requires fine surface processing, fine pattern processing and drilling using a laser beam, an electronic beam, or a diamond cutting tool, epoxy and dielectric film coating, and conductive particle application, the manufacturing process of the image drum is complicated and the manufacturing costs associated therewith are high.
In addition, in a conventional image drum, a multi-layer printed circuit board (PCB) constituting the control circuit board is connected to the ring electrode by a zebra strip by forming through holes on the drum body. Accordingly, the bonding force is low and problems may occur with the reliability of the image drum at times of high thermal stress.